There is provided an encoder and decoder for encoding and decoding input data (D1, D2 or D3) to generate corresponding encoded output data (D2 or D3, D5). The encoder includes a data processing arrangement, optionally for analyzing a range of values present in the input data (D1) to determine at least one pre- and/or post-pedestal value, optionally to translate the input data (D1) using the at least one pre- and/or post-pedestal value to generate translated data, and then to apply a form of ODelta coding to the data, optionally translated data, to generate processed data, and to combine the processed data and optionally the at least one pre- and/or post-pedestal value for generating the encoded output data (D2 or D3). The decoder includes a data processing arrangement for processing the encoded data (D2 or D3), optionally to extract therefrom at least one pre- and/or post-pedestal value.